search for: writeback

...rmat(char *prefix, int index, char *buf, int buflen) > return 0; > } > > +static int virtblk_get_cache_mode(struct virtio_device *vdev) Why are you converting u8 to int here? All users convert it back ... Also, this is not really "get cache mode" it's more of a "writeback_enabled". > +{ > + u8 writeback; > + int err; > + > + err = virtio_config_val(vdev, VIRTIO_BLK_F_CONFIG_WCE, > + offsetof(struct virtio_blk_config, wce), > + &writeback); > + if (err) > + writeback = virtio_has_feature(vdev, VIRTIO_BLK_F_WCE); > + &gt...

...rmat(char *prefix, int index, char *buf, int buflen) > return 0; > } > > +static int virtblk_get_cache_mode(struct virtio_device *vdev) Why are you converting u8 to int here? All users convert it back ... Also, this is not really "get cache mode" it's more of a "writeback_enabled". > +{ > + u8 writeback; > + int err; > + > + err = virtio_config_val(vdev, VIRTIO_BLK_F_CONFIG_WCE, > + offsetof(struct virtio_blk_config, wce), > + &writeback); > + if (err) > + writeback = virtio_has_feature(vdev, VIRTIO_BLK_F_WCE); > + &gt...

writeback_inodes_sb(_nr)_if_idle() is re-implemented by replacing down_read() with down_read_trylock() because - If ->s_umount is write locked, then the sb is not idle. That is writeback_inodes_sb(_nr)_if_idle() needn''t wait for the lock. - writeback_inodes_sb(_nr)_if_idle() grabs s_umount lock...

Well, I had the first use of the recovery mode on the RH 8.0 install CD today on a dev system. I changed the mount option for the root partition to data=writeback to see what all the claimed speed increases are about, and the system failed to mount the partition r/w, so the resulting boot failed. After search usenet, it seems other RH folks have had this problem, possibly because it is built as a module, and not into the kernel. Do I have to recompile...

...8df 100644 --- a/include/uapi/linux/virtio_blk.h +++ b/include/uapi/linux/virtio_blk.h @@ -43,11 +43,11 @@ #ifndef VIRTIO_BLK_NO_LEGACY #define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */ #define VIRTIO_BLK_F_SCSI 7 /* Supports scsi command passthru */ -#define VIRTIO_BLK_F_WCE 9 /* Writeback mode enabled after reset */ +#define VIRTIO_BLK_F_FLUSH 9 /* Writeback mode enabled after reset */ #define VIRTIO_BLK_F_CONFIG_WCE 11 /* Writeback mode available in config */ #ifndef __KERNEL__ -/* Old (deprecated) name for VIRTIO_BLK_F_WCE. */ -#define VIRTIO_BLK_F_FLUSH VIRTIO_BLK_F_WCE +/* Old...

...8df 100644 --- a/include/uapi/linux/virtio_blk.h +++ b/include/uapi/linux/virtio_blk.h @@ -43,11 +43,11 @@ #ifndef VIRTIO_BLK_NO_LEGACY #define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */ #define VIRTIO_BLK_F_SCSI 7 /* Supports scsi command passthru */ -#define VIRTIO_BLK_F_WCE 9 /* Writeback mode enabled after reset */ +#define VIRTIO_BLK_F_FLUSH 9 /* Writeback mode enabled after reset */ #define VIRTIO_BLK_F_CONFIG_WCE 11 /* Writeback mode available in config */ #ifndef __KERNEL__ -/* Old (deprecated) name for VIRTIO_BLK_F_WCE. */ -#define VIRTIO_BLK_F_FLUSH VIRTIO_BLK_F_WCE +/* Old...

Hi list, I would like to understand if, and why, the --unsafe flag is needed when using --copy-storage-all when migrating guests which uses writeback cache mode. Background: I want to live migrate guests with writeback cache from host A to host B and these hosts only have local storage (ie: no shared storage at all). From my understanding, --unsafe should be only required when migrating writeback-enabled guests between two hosts which sha...

...4d9 100644 --- a/include/uapi/linux/virtio_blk.h +++ b/include/uapi/linux/virtio_blk.h @@ -43,11 +43,11 @@ #ifndef VIRTIO_BLK_NO_LEGACY #define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */ #define VIRTIO_BLK_F_SCSI 7 /* Supports scsi command passthru */ -#define VIRTIO_BLK_F_WCE 9 /* Writeback mode enabled after reset */ +#define VIRTIO_BLK_F_FLUSH 9 /* Flush command supported */ #define VIRTIO_BLK_F_CONFIG_WCE 11 /* Writeback mode available in config */ #ifndef __KERNEL__ -/* Old (deprecated) name for VIRTIO_BLK_F_WCE. */ -#define VIRTIO_BLK_F_FLUSH VIRTIO_BLK_F_WCE +/* Old (deprecate...

...4d9 100644 --- a/include/uapi/linux/virtio_blk.h +++ b/include/uapi/linux/virtio_blk.h @@ -43,11 +43,11 @@ #ifndef VIRTIO_BLK_NO_LEGACY #define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */ #define VIRTIO_BLK_F_SCSI 7 /* Supports scsi command passthru */ -#define VIRTIO_BLK_F_WCE 9 /* Writeback mode enabled after reset */ +#define VIRTIO_BLK_F_FLUSH 9 /* Flush command supported */ #define VIRTIO_BLK_F_CONFIG_WCE 11 /* Writeback mode available in config */ #ifndef __KERNEL__ -/* Old (deprecated) name for VIRTIO_BLK_F_WCE. */ -#define VIRTIO_BLK_F_FLUSH VIRTIO_BLK_F_WCE +/* Old (deprecate...

I'm trying to enable writeback mode for the root partition. However, adding the normal option "rootflags=data=writeback" to my grub.conf kernel line doesn't result in writeback mode (according to `dmesg`). Does anyone know of a way to enable this? -Doug -- Douglas E. Warner <dwarner at ctinetworks.com&g...

Hi all, I write about libvirt inconsistent behavior when mixing io=native and cache=writeback. This post can be regarded as an extension, or clarification request, of BZ 1086704 (https://bugzilla.redhat.com/show_bug.cgi?id=1086704) On a fully upgraded CentOS6 x86-64 machine, starting a guest with io=native and cache=writeback is permitted: no errors are raised and the VM (qemu, really)...

Hello, I read some threads (some of them not very recent, and perhaps not up to date) and I have not found a clear answer to these: Is it advisable to have /tmp set up with data=writeback option in general? Is it again true if we are considering a laptop? Do I have also to consider writecache of disks in this case or are they totally non related? How to check/set the state of writecache for disks in general and in particular for laptops and what is the better configuration when we...

On Fri, Feb 17, 2017 at 02:52:06PM +0100, Gionatan Danti wrote: >Hi all, >I write about libvirt inconsistent behavior when mixing io=native and >cache=writeback. This post can be regarded as an extension, or >clarification request, of BZ 1086704 >(https://bugzilla.redhat.com/show_bug.cgi?id=1086704) > >On a fully upgraded CentOS6 x86-64 machine, starting a guest with >io=native and cache=writeback is permitted: no errors are raised and the &...

On Fri, Feb 17, 2017 at 12:33:28 +0100, Gionatan Danti wrote: > Hi list, > I would like to understand if, and why, the --unsafe flag is needed when > using --copy-storage-all when migrating guests which uses writeback > cache mode. > > Background: I want to live migrate guests with writeback cache from host > A to host B and these hosts only have local storage (ie: no shared > storage at all). > > From my understanding, --unsafe should be only required when migrating > writeback-en...

Hi everybody, I had a problem which you may be interested in. I set data=writeback in /etc/fstab for each of my ext3 partitions (because it complains on "mount -o remount,data=writeback" with "ext3: journal mode can't be altered on remount" or similar) and rebooted. Problem: / was mounted read-only, I couldn't remount it (because mount appends the opt...

...uncement on lkml, I have started using ext3 on one of my servers. Since the server in question is a farily security-sensitive box, my /usr partition is mounted read only except when I remount rw to install packages. I converted this partition to run ext3 with the mount options "nodev,ro,data=writeback,defaults" figuring that when I need to install new packages etc, that I could just mount rw as before and that metadata-only journalling would be ok for this partition as it really sees very little write activity. When I try to remount it r/w I get a log message saying: Jul 27 09:54:29 henry...

Thank you for the answer. What is the main reason of allowing this inconsistency in the td file? I guess that's because of the "some" distinction between the writeback and non-writeback versions. Is there any benefit from the inconsistency by using GRP in .td file and freezing lr and pc during register allocation in writeback version? Thanks, Junbum On May 23, 2013, at 11:51 AM, Tim Northover <tnorthover at apple.com> wrote: > Hi Junbum, > >&...

...t a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index d4d05f064d39..ea2c17c66dfb 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -478,8 +478,7 @@ static int virtblk_get_cache_mode(struct virtio_device *vdev) struct virtio_blk_config, wce, &writeback); if (err) - writeback = virtio_has_feature(vdev, VIRTIO_BLK_F_WCE) || - virtio_has_feature(vdev, VIRTIO_F_VERSION_1); + writeback = virtio_has_feature(vdev, VIRTIO_BLK_F_WCE); return writeback; } @@ -840,7 +839,7 @@ static unsigned int features_legacy[] = { static unsigned i...

...t a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index d4d05f064d39..ea2c17c66dfb 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -478,8 +478,7 @@ static int virtblk_get_cache_mode(struct virtio_device *vdev) struct virtio_blk_config, wce, &writeback); if (err) - writeback = virtio_has_feature(vdev, VIRTIO_BLK_F_WCE) || - virtio_has_feature(vdev, VIRTIO_F_VERSION_1); + writeback = virtio_has_feature(vdev, VIRTIO_BLK_F_WCE); return writeback; } @@ -840,7 +839,7 @@ static unsigned int features_legacy[] = { static unsigned i...

Hi Konrad, Sometime ago i reported this one at boot up: [ 3009.778974] mcelog:16842 map pfn expected mapping type write-back for [mem 0x0009f000-0x000a0fff], got uncached-minus [ 3009.788570] ------------[ cut here ]------------ [ 3009.798175] WARNING: at arch/x86/mm/pat.c:774 untrack_pfn+0xa1/0xb0() [ 3009.807966] Hardware name: MS-7640 [ 3009.817677] Modules linked in: [ 3009.827524] Pid: